Author Topic: EM Drive Developments - related to space flight applications - Thread 3  (Read 1803514 times)

Offline Carl G

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As had already been posted, it is not allowable to post links to download sites bypassing another site's paywall. Anyone posting such content will see their post removed and their membership banned.

Have a bit of respect for the authors of such work on these other sites.

Offline X_RaY

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....
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

aero:  please notice these helpful suggestions.  Perhaps you could try this and see whether it excites TE012 in Yang/Shell
Internet search offers several patents from MW industrie based as well on this principle.

http://www.google.com/patents/EP1000314B1?cl=en
many others are available
« Last Edit: 07/28/2015 06:37 PM by X_RaY »

Online SeeShells

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@Rodal
1.Thanks for verification (picture Tajmar device yesterday @4,556GHz).
My calculation was verry close :)

2. impressing picture of the fractal antennas... like that
But for what is that good in the frustrum? This type of antenna will be use to get large bandwide, for multiband mobilephones for example. We don't need large BW.
What is need is ~constand impedance match in the possible drift BW if a high Q is recommend like discussed before?
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

Very nice post X_Ray.  I was thinking of potentially using a 1/10 wave loop (like the square one I posted as it could be modeled) to excite a TE mode center in either center plate. The bandwidth should be around 20-30 mhz. Thoughts?

Also won't a loop on the side wall excite either mode depending on orientation?

Would love your feedback.

Shell

garbage wording.
« Last Edit: 07/28/2015 06:49 PM by SeeShells »

Offline Prunesquallor

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...

I thought of that, but for that perspective to be consistent, the big base and the small base should also be cut.  But the big base and the small base are not cut: the full perimeter circular contours (which shows as an ellipse due to the view) of the bases are fully shown.  If the waveguide would be symmetric, the full contour of the waveguide  would also be shown.   Anyway, whether the waveguide is asymmetric or whether it is symmetric and the COMSOL drawing was not consistently shown in 3D is something that perhaps Tajmar could answer after the session is over, together with confirming whether the dimensions are off by a factor of 2.

...

Neither of the photos (the table top nor the vacuum chamber) seem to indicate an offset, although it is a bit difficult to tell.
Retired, yet... not

Offline leomillert

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As had already been posted, it is not allowable to post links to download sites bypassing another site's paywall. Anyone posting such content will see their post removed and their membership banned.

Have a bit of respect for the authors of such work on these other sites.

Tajmar's paper isn't behind paywalls anymore.

It's right there on TU Dresden's website for anyone to access without restrictions.

http://tu-dresden.de/die_tu_dresden/fakultaeten/fakultaet_maschinenwesen/ilr/rfs/forschung/folder.2007-08-21.5231434330/ag_raumfahrtantriebe/JPC%20-%20Direct%20Thrust%20Measurements%20of%20an%20EM%20Drive%20and%20Evaluation%20of%20Possible%20Side-Effects.pdf
« Last Edit: 07/28/2015 07:07 PM by leomillert »

Offline deltaMass

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http://www.centauri-dreams.org/?p=33703
All About Tajmar's paper

Good to see others at the conference talking beamers too
Thanks Dr. BagelBytes for the live Reddit blog!
« Last Edit: 07/28/2015 07:15 PM by deltaMass »

Offline X_RaY

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@Rodal
1.Thanks for verification (picture Tajmar device yesterday @4,556GHz).
My calculation was verry close :)

2. impressing picture of the fractal antennas... like that
But for what is that good in the frustrum? This type of antenna will be use to get large bandwide, for multiband mobilephones for example. We don't need large BW.
What is need is ~constand impedance match in the possible drift BW if a high Q is recommend like discussed before?
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

Very nice post X_Ray.  I was thinking of potentially using a 1/10 wave loop (like the square one I posted as it could be modeled) to excite a TE mode center in either center plate. The bandwidth should be around 20-30 mhz. Thoughts?

Also won't a loop on the side wall excite either mode depending on orientation?

Would love your feedback.

Shell

garbage wording.
Can you repost a link to your setup please?
I'm a little tired today, don't wanna search...
I think up to a quater wavelength will work like you want without bigger problems.
couple the end of the loop direct to the copper( matching capacitor will also work between loops end and copper).
Dipoles very close to the wall will work also.
Picture:
In general,pace the antenna in one of the positions like in the sketch.
« Last Edit: 07/28/2015 07:17 PM by X_RaY »

Online Rodal

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http://www.centauri-dreams.org/?p=33703
All About Tajmar's paper

Good to see others at the conference talking beamers too
Thanks Dr. BagelBytes for the live Reddit blog!

So Tajmar previously NULLIFIED the claims of Prof. Woodward according to this quote ?:

Quote
Martin Tajmar did an independent series of replication experiments on work performed by James Woodward (the ‘Woodward effect’), while working at the Austrian Research Center’s department of electric propulsion physics. While that work produced a null result,

and Heidi Fearn this afternoon is going to be presenting a paper sandwiched between Tajmar's papers? A paper about more Woodward tests that Tajmar has nullified ?

So it looks like the EM Drive was not as easy to nullify as Woodward's claims ?
« Last Edit: 07/28/2015 07:21 PM by Rodal »

Offline deltaMass

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http://www.centauri-dreams.org/?p=33703
All About Tajmar's paper

Good to see others at the conference talking beamers too
Thanks Dr. BagelBytes for the live Reddit blog!

So Tajmar previously NULLIFIED the claims of Prof. Woodward according to this quote ?:

Quote
Martin Tajmar did an independent series of replication experiments on work performed by James Woodward (the ‘Woodward effect’), while working at the Austrian Research Center’s department of electric propulsion physics. While that work produced a null result,

and Heidi Fearn this afternoon is going to be presenting a paper sandwiched between Tajmar's papers? A paper about more Woodward tests that Tajmar has nullified ?

So it looks like the EM Drive was not as easy to nullify as Woodward's claims ?
I was there when Jim and Martin put their heads together before Martin's presentation. Martin was as kind as he could be. He worked in Jim's lab at one point, even.

The propellantless propulsion universe isn't that big.
« Last Edit: 07/28/2015 07:23 PM by deltaMass »

Online SeeShells

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@Rodal
1.Thanks for verification (picture Tajmar device yesterday @4,556GHz).
My calculation was verry close :)

2. impressing picture of the fractal antennas... like that
But for what is that good in the frustrum? This type of antenna will be use to get large bandwide, for multiband mobilephones for example. We don't need large BW.
What is need is ~constand impedance match in the possible drift BW if a high Q is recommend like discussed before?
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

Very nice post X_Ray.  I was thinking of potentially using a 1/10 wave loop (like the square one I posted as it could be modeled) to excite a TE mode center in either center plate. The bandwidth should be around 20-30 mhz. Thoughts?

Also won't a loop on the side wall excite either mode depending on orientation?

Would love your feedback.

Shell

garbage wording.
Can you repost a link to your setup please?
I'm a little tired today, don't wanna search...
I think up to a quater wavelength will work like you want without bigger problems.
couple the end of the loop direct to the copper( matching capacitor will also work between loops end and copper)
Picture:
In general,pace the antenna in one of the positions like in the sketch.

Mode Shape TE012   
Length 0.24   
big diameter 0.201   
small diameter 0.1492      
cone 1/2 angle 6.159   
In Meters

Get something cold with ice, prop you feet up and relax. Sounds like a yucky day. Thanks for doing this after a hard day.

Shell
« Last Edit: 07/28/2015 07:26 PM by SeeShells »

Online Rodal

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CalTech's Prof. Sean Carroll's scholastic review of Tajmar's EM Drive paper and the EM drive in general:

Quote
“My insight is that the EMDrive is complete crap and a waste of time,” Carroll tells io9. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.” 

http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

also further critical comments from Eric Davis and Millis (ex NASA)
« Last Edit: 07/28/2015 07:31 PM by Rodal »

Offline Prunesquallor

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Prof. Sean Carroll's scholastic review of Tajmar's EM Drive paper and the EM drive in general:

Quote
“My insight is that the EMDrive is complete crap and a waste of time,” Carroll tells io9. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.” 

http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

together with further comments from Eric Davis and Millis (ex NASA)

When supposedly intelligence folks use phrasing like that, I tend to dismiss what they are saying.  To me it indicates close-mindedness and lazy intellect.
Retired, yet... not

Offline deltaMass

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Prof. Sean Carroll's scholastic review of Tajmar's EM Drive paper and the EM drive in general:

Quote
“My insight is that the EMDrive is complete crap and a waste of time,” Carroll tells io9. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.” 

http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

also further critical comments from Eric Davis and Millis (ex NASA)
The fur is flying today!  8)

Online SeeShells

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Prof. Sean Carroll's scholastic review of Tajmar's EM Drive paper and the EM drive in general:

Quote
“My insight is that the EMDrive is complete crap and a waste of time,” Carroll tells io9. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.” 

http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

also further critical comments from Eric Davis and Millis (ex NASA)
"It is the mark of an educated mind to be able to entertain a thought without accepting it." - Aristotle

Offline Star One

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CalTech's Prof. Sean Carroll's scholastic review of Tajmar's EM Drive paper and the EM drive in general:

Quote
“My insight is that the EMDrive is complete crap and a waste of time,” Carroll tells io9. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.” 

http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

also further critical comments from Eric Davis and Millis (ex NASA)

Same old, same old like a stuck record & using such base language does them no favours either.

Offline Chrochne

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News wave about the latest development of the EmDrive
« Reply #5515 on: 07/28/2015 07:37 PM »
Internet is really getting wild about the latest development about the EmDrive. I see a lot of new posts. Only few are sceptical so far.

I found one post today that already have 26 thousand shares just today. It usually triples in two more days. http://www.sciencealert.com/independent-scientists-confirm-that-the-impossible-em-drive-produces-thrust
This actually may hit major news.

Dr. BagelBites dont get eaten by the newspaper guys there. We would surely miss you.

Here is that sceptical article. It is sceptical but actualy have over 18 thousands shares already and 2 thousand plus visitors just this hour. http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809
« Last Edit: 07/28/2015 07:38 PM by Chrochne »

Offline X_RaY

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@Rodal
1.Thanks for verification (picture Tajmar device yesterday @4,556GHz).
My calculation was verry close :)

2. impressing picture of the fractal antennas... like that
But for what is that good in the frustrum? This type of antenna will be use to get large bandwide, for multiband mobilephones for example. We don't need large BW.
What is need is ~constand impedance match in the possible drift BW if a high Q is recommend like discussed before?
 
3.
"3) We also verified that one cannot excite Transverse Electric (TE) modes with a dipole antenna, regardless of orientation or placement in the truncated cone, the mode excited by a dipole antenna is a Transverse Magnetic (TM) mode."

At the center it doesn't work.

I remember that is possible to get TE resonance with a simple dipole:
(rfmwguy posted something similar / plans for his frustrum...)
 It's most simple for TE01p. At this mode there are currents in Phi vector inside the metallic endplate, the strongest at the radius who the besselfunktion is maximal.
Place a dipole at this radius close to the plate, E-field vector in Phi direction(tangetial to the radius).
The result will be the correct mode if the cone has the correct length to catch that eigenfrequence.

Something similar is possible at the sidewall, one have to activate currents in the right direction for the mode in the wall..
of course one need a full 3D model

very interesting posts today too much to read all after long day full of work  :-[

Very nice post X_Ray.  I was thinking of potentially using a 1/10 wave loop (like the square one I posted as it could be modeled) to excite a TE mode center in either center plate. The bandwidth should be around 20-30 mhz. Thoughts?

Also won't a loop on the side wall excite either mode depending on orientation?

Would love your feedback.

Shell

garbage wording.
Can you repost a link to your setup please?
I'm a little tired today, don't wanna search...
I think up to a quater wavelength will work like you want without bigger problems.
couple the end of the loop direct to the copper( matching capacitor will also work between loops end and copper)
Picture:
In general,pace the antenna in one of the positions like in the sketch.

Mode Shape TE012   
Length 0.24   
big diameter 0.201   
small diameter 0.1492      
cone 1/2 angle 6.159   
In Meters

Get something cold with ice, prop you feet up and relax. Sounds like a yucky day. Thanks for doing this after a hard day.

Shell
I get 2,449GHz for TE012 with this dimensions(flat end plates)   :D
surface conductivity is lower in your case(perforated copper), the antenna also cause a tiny frequency shift, it will be a little less than the eigenfrequency ;) ~10...100MHz lower is possible i think
Try it, we will see.
 :)
Can you measure S11 when your build is done? I'm curious about the data.

 2,4490862069GHz
« Last Edit: 07/28/2015 07:57 PM by X_RaY »

Online Rodal

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...

I get 2,449GHz for TE012 with this dimensions(flat end plates)   :D
surface conductivity is lower in your case(perforated copper), the antenna also cause a frequency shift, it will be a little less than the eigenfrequency ;) ~10...100MHz lower is possible i think
Try it, we will see.
 :)
Can you measure S11 when your build is ready?

Excellent. Actually your numbers seem to agree with mine closer than TheTraveller's calculations
« Last Edit: 07/28/2015 07:48 PM by Rodal »

Offline Star One

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Internet is really getting wild about the latest development about the EmDrive. I see a lot of new posts. Only few are sceptical so far.

I found one post today that already have 26 thousand shares just today. It usually triples in two more days. http://www.sciencealert.com/independent-scientists-confirm-that-the-impossible-em-drive-produces-thrust
This actually may hit major news.

Dr. BagelBites dont get eaten by the newspaper guys there. We would surely miss you.

Here is that sceptical article. It is sceptical but actualy have over 18 thousands shares already and 2 thousand plus visitors just this hour. http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

Great just what we don't need an invasion of the believers & sceptics again.:(

Offline Chrochne

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Internet is really getting wild about the latest development about the EmDrive. I see a lot of new posts. Only few are sceptical so far.

I found one post today that already have 26 thousand shares just today. It usually triples in two more days. http://www.sciencealert.com/independent-scientists-confirm-that-the-impossible-em-drive-produces-thrust
This actually may hit major news.

Dr. BagelBites dont get eaten by the newspaper guys there. We would surely miss you.

Here is that sceptical article. It is sceptical but actualy have over 18 thousands shares already and 2 thousand plus visitors just this hour. http://io9.com/no-german-scientists-have-not-confirmed-the-impossibl-1720573809

Great just what we don't need an invasion of the believers & sceptics again.:(

I hear you there Mr. Star One

Sean Caroll reaction to latest development  http://www.outerplaces.com/science/item/9455-impossible-and-controversial-em-drive-can-get-us-to-the-moon-in-four-hours

“My insight is that the EMDrive is complete crap and a waste of time,” said Carroll. “Right there in the abstract this paper says, ‘Our test campaign can not confirm or refute the claims of the EMDrive’, so I’m not sure what the news is. I’m going to spend my time thinking about ideas that don’t violate conservation of momentum.”

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